STRESS ANALYSIS OF HALF TOROIDAL CONTINUOUSLY VARIABLE TRANSMISSION SYSTEM

The continuously variable transmission, or CVT, continues to emerge as a key technology for improving the fuel efficiency of automobiles with internal combustion (IC) engines. A toroidal continuously variable transmission (CVT) has an elliptical shape in the contact area, which resulting high contact stress and transmits the power. Many parameters affect the contact stress of the half toroidal CVT, which include the properties of the contacting material (Young’s modulus), operating parameter (input load) and geometrical parameters (aspect cavity ratio, curvature ratio and half cone angle of the power roller, transmission ratio). In this paper, the contact between the input disk and the power roller are formulated using the classical Hertzian contact theory. Based on the formulated equations, different system parameters, which affect the maximum Hertzian contact stresses, are compared with the simulated results generated in ANSYS. The comparative results will provide some observations of the relations between the maximum Hertzian stresses and input load in the form of graphs for different materials (i.e. 100Cr6/Si3Ni4, 100Cr6/Ni75%, Cr 14%, Fe 10%, 100Cr6/100Cr6, 100Cr6/Ni70 %, Cu 30 %). These graphs give useful information for designer to know the maximum Hertzian stress during operation in such systems.